EDN1 and interstitial lung disease: Three biomarkers were associated with ILD progression at 1 year: CXCL4 [odds ratio (OR) 2.67, 1.46–4.88, 1.67; P = 0.001], MMP-1 (OR 2.56, 1.43–4.59; P = 0.002) and ET-1 (OR 2.18, 1.24–3.83; P = 0.007).